Omni angle rotary table

ABSTRACT

An omni angle rotary table having a cam cylinder with an angularly disposed cam surface on its end, and a shaft which is axially and rotatably disposed with respect to the cam cylinder. A platform assembly is pivotally affixed to the end of the shaft and supports cam means which slidably engage with the cam surface on the cam cylinder, so that the platform assembly is caused to rotate and to pivot back and forth as the shaft and/or cam cylinder is rotated.

llrte Stats [191 [111 3,828,727 auerle Aug. 13, R974 OMNl ANGLE ROTARY TABLE 3,749,052 7/1973 Porter 118/53 x [76] Inventor: John ll. Bauerle, 208 S.W, St., P E R L k rzmary xammer 0y a e Mansfield 61854 Assistant ExaminerMark S. Bicks [22] Filed: Apr. 23, 1973 Attorney, Agent, or Firm-Dominik, Knechtel, Godula 21 App]. No.: 353,302

57 ABSTRACT [52] US. Cl 118/500, 118/53, 269/55 1 [51] Int. Cl. B05c 111/12 An 0mm angle,rotary table havmg a cylinder [58] Field at Search 8/48 49 491 495 an angularly drsposed cam surface on its end, and a [18/53 56 321 6 3 259/8 shaft which is axially and rotatably disposed with re- 89 Z 58 62 spect to the cam cylinder A platform assembly is pivotally affixed to the end of the shaft and supports cam [56] References Cited means which slidably engage with the cam surface on the cam cylinder, so that the platform assembly is UNITED STATES PATENTS caused to rotate and to pivot back and forth as the lg; il i yg 2 shaft and/or cam cylinder is rotated. c e0 3,332,392 7/1967 Gessner 118/503 X 11 Claims, 4 Drawing Figures PAIENIEO AUBI 3:914

m 2 9 i 6 2 E W 1w] a m. by? m70\. u k 3 7 a w W H n I 2 z w 6 F a :1! m I H o l a n w m w v OMNI ANGLE ROTARY TABLE SUMMARY OF THE INVENTION This invention relates to an improved omni angle rotary table.

The omni angle rotary table of the present invention is particularly adapted for use in coating irregular specimens with a uniform carbon or metallic coating in a vacuum evaporator, for subsequent observation in a scanning electron microscope. The motion of the table presents the specimen to the metal vapor being deposited at all angles. Higher resolution photographs can be obtained than is possible with other methods because of the uniformity of the evaporated layer in all the sur face irregularities of the specimen.

The direct action of the cam surface on the tables platform and the virtually balanced condition of the platform results in a unit that sweeps a wider excursion with much less wear than other similar commercially available units. Its simplicity lends itself to a low manufacturing cost and low power requirement for operation with an increase in efficiency over the same similar commercially available units.

The design of the omni angle rotary table also is such that the specimen can be adjusted initially so it faces the vapor source in its median position. Also, a platen holding a number of specimens may be used in place of a single slide, enabling the operator to coat many specimens uniformally in one operation.

Accordingly, it is an object of the present invention to provide an improved omni angle rotary table.

Another object of the invention is to provide an improved omni angle rotary table having a 60 angle of excursion, 30 either side of center.

Still another object is to provide an improved omni angle rotary table of the above type having a ratio of approximately 3% tilts to l revolution, with the same being designed such that this ratio may be maintained with little wear.

Further still, it is an object to provide an improved omni angle rotary table having a virtually balanced platen which is pivoted in the center of the platen, in line with the cam faces thereof. In this respect, no springs are used, thus little wear on the cam shoes results.

Still another object is to provide an improved omni angle rotary table wherein slight wear on the cam shoes or cam surface thereof shows up as looseness, not detrimental to the function of the table, which wear or looseness can be easily and quickly compensated for.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:

FIG. 1 is a side plan view of the omni angle rotary table;

FIG. 2 is an end plan view of the omni angle rotary table, partially sectionalized to illustrate its construc tion;

FIG. 3 is a side plan view of the omni angle rotary table, with a drive mechanism attached thereto; and

FIG. 4 is a top plan view of a multi specimen holder. Similar reference characters refer to similar parts throughout the several views of the drawings.

DESCRIPTION OF THE INVENTION Referring now to the drawing, particularly FIGS. 1 and 2 thereof, the omni angle rotary table 10 is shown and can be seen to include a shaft 11 which is retained and rotatably supported in a vertically disposed position by means of a bracket 12 fixedly secured to a supporting surface 13. The bracket 12 includes two ball bearings (not shown) which are stacked and in which the shaft 11 rotates. The bracket 12 further has elongated slots (not shown) formed in it through which the threaded bolts 43 extend. These slots permit the pulley belt tension to be adjusted. A rotational pulley 14 is secured to the shaft 11 by means of a set screw 15, for rotating the shaft 11 in the manner described more particularly below.

A cam cylinder 16 which is generally of a solid cylindrical configuration having a bore 18 extending axially through it for receiving the shaft 11 is rotatably supported atop the rotational pulley 14. A scan pulley or groove 17 is formed in the peripheral surface of the cam cylinder 16, preferably adjacent the lower end thereof, and a bearing cavity 20 is provided in the lower end for receiving a bearing race 21. A similar bearing race 44 is disposed with a cavity 45 in the upper end of the cam cylinder, for supporting the shaft 11. A thrust washer 32 preferably and advantageously is provided between the rotational pulley 14 and the cam cylinder 16, to permit them to rotate at different speeds without rubbing, as described more particularly below. The upper end of the cam cylinder 16 is tapered to provide a cam surface which is at an angle of approximately 30. A tilting platform 22 is pivotally secured by means of a pivot pin 25 to the upper end of the shaft 11 and supports two laterally positioned cam shoes 23 and 2 4. These cam shoes 23 and 24 preferably and advantageously are of teflon or other similar material, and are disposed to ride on the cam surface 19 on the cam cylinder 16.

A slide holder or platform 26 has a generally U- shaped bracket 27 fixedly secured below and centrally positioned between the opposite ends thereof, for affixing the slide holder 26 to the tilting platform 22. The latter is received between the two downwardly depending arms of the U-shaped bracket 27, and the bracket 27 and the tilting platform 22 are adjustably affixed together by means of threaded screws 28. With this construction, the slide holder 26 can be pre-set in a horizontal position, as illustrated, or at an initial angle up to and slightly in excess of 30, by merely loosening the threaded screws 28, adjusting the angle and then retightening the threaded screws 28 to secure the slide holder 26 in the angularly adjusted position.

The slide holder 26 preferably is of dimension such that a glass slide 29 of the dimensions normally used in most laboratories can be supported and retained atop of it. For this purpose, the opposite ends of the slide holder 26 are reversely bent to form channels 33 into which the glass slide can be slidably extended to engage a pair of stops 41. A spring steel locking lever 31 is, provided for locking the glass slide 29 in position atop the slide holder 26. To remove the glass slide 29, the outwardly extending terminal end of the locking lever 31 is pressed down to permit the glass slide 29 to be removed by sliding it out of the U-shaped channels 33. A glass slide 29 of the type illustrated is generally used to support a specimen 30, as illustrated in FIG. 3, which is to be coated in a vacuum evaporator.

From the above-described construction of the omni angle rotary table 10, it can be seen that when the rotational pulley 14 is rotated, the shaft 11 and the tilting platform 22 and the slide holder 26 affixed to its upper end is rotated with it. As the shaft 11 rotates, the cam shoes 23 and 24 ride on the cam surface 19 on the cam cylinder 16, thus causing the tilting platform 22 and the slide holder 26 to tilt back and forth through a 60 angle of excursion, 30 either side of center of the end of the shaft 1 1. An oscillating motion is imparted to the slide holder 26, by rotating the cam cylinder 16. In this respect, the rotational pulley l4 and the scan pulley 17 are proportionally sized to provide a ratio of approximately 3% tilts to l revolution. Various methods can be used to drive the omni angle rotary table 10, such as, for example, by use of friction wheels, gears, a direct drive from a motor shaft, or by means of rubber drive belts 37 and 38 which are in turn rotatably driven by means of a variable speed motor 34 having pulleys 35 and 36 affixed to its drive shaft. Rubber drive belts such as those illustrated are preferred over a chain and sprocket type drive, since the rubber drive belts have no slack and therefore run the table more smoothly, whereas the chain and sprockets run rough and it is difficult to keep both chains tight.

Since the pivot point for the tilting platform 22 and the slide holder 26 affixed to it is on the end of the shaft 11 and centrally or axially positioned to or with the cam surface 19, there is very little wear on the cam shoes 23 and 24. Furthermore, this provides a virtually balanced slide holder 26, so that there is an even load on the drive motor 34. Even loading of the slide holder 26 results only in added weight to be oscillated, but the latter will still be balanced. Any slight wear which does result on the cam shoes 23 and 24 only shows up as looseness which can be easily and quickly compensated for, simply by loosening the set screw and raising the rotational pulley l4 and the cam cylinder 16 with respect to the cam shoes 23 and 24.

The initial angle of tilt of the slide holder 26 can be adjusted from the horizontal position shown, to any angle up to approximately 30 by simply loosening the threaded screws 28 and adjustably positioning the slideholder 26 with respect to the tilting platform 22. Thereafter the threaded screws 28 are tightened to secure the slide holder 26 in the adjusted position. The rotational pulley l4 and the cam cylinder 16 also may be locked together at any position, by means of a set screw 50, a pin or even a piece of rubber wedged between them, and one belt removed to permit the table to be used as an adjustable rotary turntable, with additional tilt available at the pivot on the slide holder 26. When driven in this fashion, the slide holder 26 can be adjusted to provide an initial angle in excess of 30.

A multi specimen slide holder 39 having a number of apertures 40 (21 apertures in the illustrated example) formed in it for supporting a number of specimens also can be removably secured to the slide holder 26, by

means of a bracket with the approximate dimensions of the glass slide, in place of the glass slide 29. When the multi specimen slide 39 is used, an operator may coat many specimens uniformally in one operation.

From the above description, it can be seen that the omni angle rotary table 10 functions in a manner that sweeps the specimen on the glass slide 29 affixed to the slide holder 26 back and forth through a 60 are several times per revolution. This motion will present the specimen to the metal vapor being deposited at all angles so that there is greater uniformity of the evaporated layer on all of the surface irregularities of the specimen. The

direct action of the cam surface on the slide holder 26- and the virtually balanced condition of the table results in a unit that sweeps a wider excursion with much less wear, particularly in comparison to other similar types of units commercially available. Further still, its simplicity lends itself to a low manufacturing cost and low power requirements for operation with an increase in efficiency over these other commercially available units.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and certain changes may be made in the above construction. Accordingly,

it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. An omni angle rotary table comprising, in combination: a shaft supported for rotation; a cam axially and rotatably disposed about said shaft and having one end thereof tapered to provide an angularly disposed cam surface; a platform assembly pivotally secured to the end of said shaft and having cam means slidably engaged with said cam surface on said cam; said platform assembly being caused to rotate and to tilt back and forth through an arc of excursion as said shaft is rotated relative to said cam.

2. The omni angle rotary table of claim 1, wherein both said shaft and said cam are rotated, whereby said platform assembly rotates and tilts in an oscillatory pattern.

3. The omni angle rotary table of chain 2, wherein said shaft and said cam are rotated at respective rates of speed such that several tilt cycles occur for each rotational cycle.

4. The omni angle rotary table of claim 2, wherein said shaft and said cam are rotated so that the resulting oscillatory pattern is not reentrant.

5. The omni angle rotary table of claim 2, wherein said cam means comprises a pair of cam shoes laterally disposed on opposite sides of said shaft and arranged to slidably engage on said cam surface.

6. The omni angle rotary table of claim 2, wherein said cam is adjustable with respect to said platform assembly to compensate for any wear on said cam means.

7. The omni angle rotary table of claim 2, wherein said platform assembly comprises a tilting platform pivotally affixed to the end of said shaft and a platen adjustably secured to said tilting platform, whereby said platen can be initially adjusted at a pre-determined angle of tilt.

8. The omni angle rotary table of claim 2, wherein said cam surface is at an angle of approximately 30, and said platform assembly tilts back and forth through an arc of excursion of approximately 60, 30 either side of center.

impairments.

11. The omni angle rotary table of claim 1, wherein said shaft and said cam can be locked together at any position and driven together for use as an adjustable rotary turntable. 

1. An omni angle rotary table comprising, in combination: a shaft supported for rotation; a cam axially and rotatably disposed about said shaft and having one end thereof tapered to provide an angularly disposed cam surface; a platform assembly pivotally secured to the end of said shaft and having cam means slidably engaged with said cam surface on said cam; said platform assembly being caused to rotate and to tilt back and forth through an arc of excursion as said shaft is rotated relative to said cam.
 2. The omni angle rotary table of claim 1, wherein both said shaft and said cam are rotated, whereby said platform assembly rotates and tilts in an oscillatory pattern.
 3. The omni angle rotary table of chain 2, wherein said shaft and said cam are rotated at respective rates of speed such that several tilt cycles occur for each rotational cycle.
 4. The omni angle rotary table of claim 2, wherein said shaft and said cam are rotated so that the resulting oscillatory pattern is not reentrant.
 5. The omni angle rotary table of claim 2, wherein said cam means comprises a pair of cam shoes laterally disposed on opposite sides of said shaft and arranged to slidably engage on said cam surface.
 6. The omni angle rotary table of claim 2, wherein said cam is adjustable with respect to said platform assembly to compensate for any wear on said cam means.
 7. The omni angle rotary table of claim 2, wherein said platform assembly comprises a tilting platform pivotally affixed to the end of said shaft and a platen adjustably secured to said tilting platform, whereby said platen can be initially adjusted at a pre-determined angle of tilt.
 8. The omni angle rotary table of claim 2, wherein said cam surface is at an angle of approximately 30*, and said platform assembly tilts back and forth through an arc of excursion of approximately 60*, 30* either side of center.
 9. The omni angle rotary table of claim 2, wherein said shaft and said cam both are adapted to be driven by means of rubber drive belts.
 10. The omni angle rotary table of claim 2, wherein said platform assembly is affixed to said shaft by an axial pivot in line with the cam surfaces so as to provide a virtually balanced assembly, free of springs or other impairments.
 11. The omni angle rotary table of claim 1, wherein said shaft and said cam can be locked together at any position and driven together for use as an adjustable rotary turntable. 